1. Field of the Invention
The present invention relates to a technique for performing information processing using a plurality of processors, and more concretely relates to (for example) a memory control device that is installed in a RAID (redundant array of independent inexpensive disks) system.
2. Description of the Related Art
One type of device for performing information processing using a plurality of processors is (for example) a memory control device which controls access from a host device to a memory device that has a plurality of physical disks arranged in the form of an array. For example, two or more channel adapters that are used for communications with the host device and two or more disk adapters that are used for communications with the memory device are installed in the memory control device. One or more microprocessors (hereafter abbreviated to “MP”) are installed in each of the adapters.
Control information is exchanged between the MPs mounted in the channel adapters (hereafter referred to as “channel MPs”) and the MPs mounted in the disk adapters (hereafter referred to as “disk MPs”). For example, in the technique disclosed in Japanese Patent Application Laid-Open No. 2001-306265 (e. g., paragraph 44), the exchange of control information between the channel MP 17 and disk MP 21 is accomplished via a shared memory 32. In concrete terms, for example, when control information is sent from the channel MP 17 to the disk MP 21, the channel MP 17 writes control information into a specified region of the shared memory 32; meanwhile, the disk MP 21 periodically polls this specified region of the shared memory 32, and if there is control information in this specified, region, the disk MP 21 acquires the control information from this specified region.